Method of treating waters



United States Patent METHOD OF TREATING WATERS, INCLUDING BOILER WATERS, AND COMPOSITION THERE- FOR Wayne L. Denman, Oak Park, Ill., assignor to Dearborn Chemical Company, Chicago, 111., a corporation of Illinois No Drawing. Orig'ual No. 2,400,543, dated May 21, 1946, Serial No. 321,140, February 27, 1940. Reissue No. 23,614, dated January 13, 1953, Serial No. 274,520, March 1, 1952. This application for reissue October 25, 1957, Serial No. 692,963

31 Claims. (Cl. 210-59) Matter enclosed in heavy brackets II] appears in the first but forms no part of this reissue specification; matter printed in italics indicates the additions made by the first reissue; matter printed in bold face indicates the additions made by this reissue.

The present invention relates to the treatment of waters, or aqueous baths, having present ingredients inducing lfoaming. More particularly, 'waters of the above character are treated with amines or more especially aliphatic amines, which are sparingly soluble, or substantially insoluble in the Water being treated, preferably do not steam distill to any substantial extent, and exhibit little tendency to saponify with the ingredients of the water or aqueous bath.

The invention, in its narrower form, contemplates the treatment of waters with saturated and/or unsaturated aliphatic amines, said compounds containing eleven (11) or more carbon atoms, being substantially insoluble in water, and showing little tendency to steam distill. In the more specific form of the invention, said compounds are used to inhibit the foaming tendency of raw or softened alkaline waters and particularly boiler waters having excess alkalinity, or an alkalinity present in a quantity more than sutficient to combine with the calcium and/or magnesium ions, salts or their equivalents contained in the water.

7 It may be stated that the solubility of the aliphatic amines in water decreases with the molecular weight thereof, and, therefore, in accordance with the present invention, it is preferred to use those amine compounds which have a high molecular weight, and by this is meant compounds having eleven (11) carbon atoms or more, and typified by undecyl amine, dodecyl amine, tridecyl amine, and the like, these all being straight chain primary amines.

As previously pointed out, aliphatic amines which are sparingly soluble, or substantially insoluble, maybe used as the primary anti-foam agent in a composition adapted to inhibit the foaming in waters containing ingredients inducing foaming therein. These amines are particularly capable of giving satisfactory results in inhibiting the foaming tendency of waters containing excess alkalinity, and particularly excess sodium and potassium alkalinity. These amines as a group show substantially no tendency to saponify in the Water or aqueous bath treated. Pref erably, where the Water treated is subjected to a high temperature, the aliphatic amines should not steam distill to any material extent. Examples of aliphatic amines which may be used in accordance with the present invention are hexadecyl amine (C H NH heptadecyl amine (C H NH octadecyl amine (c gHaqNHz), and secondary octyl amine (C H NHC H It may be pointed out that in accordance with the present invention, it is the intention to use the broad class of amines, either aliphatic or aromatic, which are sparingly soluble, orsubstantially insoluble in water, and

which prevent the foaming of the water or the aqueous bath treated. Generally, it is the amines of high molecular weight which are the most satisfactory, and as a general rule, it may be stated that the most insoluble ones are the amines which contain more than ten (10) carbon atoms, particularly the straight chain primary amines. However, it may be pointed out that the split chain primary amines, as well as the straight chain and split chain secondary and tertiary amines, may be used in accordance with the present invention.

Other straight chain primary amines which may be used as an anti-foam agent are:

Undecyl BIIIIDE (CnHggNHg) Dodecyl amine (C H NH Tridecyl amine (C H NH Tetradecyl amine (C14H29NH2) Pentadecyl amine (C, H NH,) Nonadecyl amine (C H NH Eicosyl amine (C II NH Heneicosyl amine (C H NH Docosyl amine (C H NH Tricosyl amine (C H NH Tetracosyl amine (C H NH Pentacosyl amine (C H NH Hexacosyl amine (C H NH Heptacosyl amine (C H NH Octacosyl. amine (C H NH Nonacosyl amine (C H NH,)

and the like.

Several of the above amines are known under other names, as for example lauryl amine (C H NH myristyl amine (C H NH mellisyl .amine and cerotyl amine (C H NH It is within the province of the present invention to use the isomeric forms of the straight chain amines or any other amines which are sparingly soluble or sub- Ethyloctylmethyl amine,

CH (CH qCHNHgCHgCHa Propylheptylmethylamine, I

CH (CH ,CHNH, (CH cH Butylhexylmethylamine,

3 2 s a 2) a a Diamyl methyl amine,

CH CH (:HNH, 0H ,cH,

Similar isomeric amines may be prepared from other normal straight chain amines.

Secondary amines which are suitable for carrying out the present invention are:

Secondary heptylamine, c7H15HNC7Hj5 Secondary octyl amine, C H NHC H Tertiary amines suitable for carrying out the present invention are:

Tertiary octylamine, (C H N Tertiary heptylamine, (C7H15)3N I SO BI a) I Secondary and tertiary amines typified by the above mentioned amines have a number of isomeric forms which may be used in carrying out the present invention. Unbalanced straight chains or split chains result in many isomers for each amine having. all alkyl groups the same.

Irrespective of to which carbon atom the amine group is attached, the material is a straight chain primary amine. Not only is it possible to use straight chain and split chain secondary and tertiary amines, but the isomeric forms of such amines may be used, and these compounds may differ from each other only in having an alkyl group substituted for one or both of. the hydrogens in the amine group. If one hydrogen is substituted for, it would of course, be a secondary amine, and if both of the hydrog eiis are substituted for, it would-be a tertiary amine. Substituting alkyl groups for hydrogens in the amine group, would tend to result in products of lower water solubility. However, the point is here made that the amine, irrespective of the substitution that has been made, should be one that has negligibie Water solubility. Further, the amines herein disclosed should preferably have a specific gravity less than water, so as to eliminate any tendency of the anti-foam agents to settle to the bottom of the treatment vessel.

Very satisfactory results have been obtained when the present invention has been applied to waters containing sodium or potassium alkalinity, that is, water in which the sodium or potassium alkalies or their equivalents, and particularly sodium or potassium hydroxides, carbonates or bicarbonates, exist in excess of that capable of combining with or existing in combination with calcium and/ or magnesium-ions present in the water.

Alkalinity of this type can exist naturally in the water or. may be derived from zeolite treatment of the water, or may be derived in other ways.

The present invention may be applied to raw waters either hard or soft and beneficial results obtained. Water, which has been softened by the lime-soda-ash process or by phosphates, sodium silicates, or other alkaline treatment, may be treated with an anti-foam composition of the character herein set forth.

It is well known that many substances have decided I anti-foam properties when used in conjunction with normal types of water which are free from excess alkalinity,

such as sodium alkalinity, or which have a low percentage of sodium alkalinity. Castor oil and sperm oil typify such substances.

When materials of this type are added to Waters of excess alkalinity, and especially excess sodium and/or potassium alkalinity, poor or mediocre results are obtained in reducing the foaming tendency of the water. It seems probable that the foaming occurring in boiler water is the result of the concentration of soluble salts and insoluble solids in a state of suspension. In waters of excess alkalinity there may be present sodium and/or potassium bi-carbonates and/or carbonates, and there may be present sodium and/or potassium carbonates and/or hydroxides. Under conditions prevailing in an operating boiler, a large percentage of the bi-carbonates and carbonates originally present in the Water are converted into hydroxides. It may well be that because of the presence of these hydroxides that the usual anti-foam materials are ineffective when added to boiler waters having high or moderately high concentrations of alkali hydroxides or other alkali materials.

When oils of the above type are added to boiler water,

i there is a tendency. for them to be saponified or react chemically with the alkali hydroxides or other alkali compounds, with the resultant formation of soluble sodium and/or potassium soaps. The foaming tendencies of sodium and potassium soaps are well recognized and the formation of such soaps accelerate the tendencies of the boiler water to foam.

The following is a specific example, illustrating such acceleration and foaming. tendency. An experimental not" steam distill toany marked degree.

' boiler operating at a pressure of 2G0 lbs. per square inch,

with an excess caustic alkalinity in the neighborhood of 200 grains per gallon, was treated with a standard antifoam material containing 16% of castor oil by weight, the proportion being one-quarter pound of the castor oil material per 1000 gallons of water. immediately after the introduction of the anti-foam material, a test showed no foaming occurring. One hour after the introduction of the anti-foam material, the amount of foaming occurring was approximately 25% greater than that taking place before the anti-foam material was added. The increase in foaming occurring one hour after the introduction of the anti-foam material, namely, castor oil, is due to the saponification of the same by the alkalies present in the boiler water.

Steam distillation of the usual anti-foam materials may, in some measure, reduce the effectiveness of these antifoam materials in boiler water of high or excess sodium or equivalent alkalinity. However, since most of the usual anti-foam materials can he used effectively in water containing little or no sodium alkalinity, and their effectiveness maintained, to a large degree at least, for several hours, steam distillation of the anti-foam material is probably of minor importance.

in one form of the present invention, water containing alkalinity, and particularly sodium or potassium alkalinity,- is treated with a material that is unsaponifiable and does Waters softened by base exchange processes, and especially those which have been treated with zeolites or waters having a high natural sodium carbonate or sodium lei-carbonate alkalinity are typical of waters having foaming properties and which may be treated in accordance with the present invention, which resides not only in said method, but also in. the utilization of a particular class of anti-foam materials, and the method of preparing the same. While the average operating boiler pressure is around 200 pounds per square inch, it is to be understood that the present invention is applicable to boiler pressures materially higher or lower than 200 pounds per square inch.

The amines of the present invention may be mixed with adispersing agent, and in the narrower form of the inven tion, the preferred dispersing agent is tannin, as will be hereinafter more fully pointed out.

it may be stated that three principal typical classes of dispersing agents are available. The first class comprises inorganic colloidal material, such as clays or bentonite;

the second class, organic material which contain appreciable quantities of soap in one form or another; and the third class, organic materials which are characterized by colloidal properties and which contain no soap of any kind. This third class of materials includes the extracts of various woods and barks which would normally be referred to as tannin extracts; extracts of various aquatic plants, such as seaweeds or kelp; and extracts of certain plants and shrubs, such as cactus plants.

Clays or bentonite may, of course, be used, but the disadvantages of this type of material makes it inadvisable to use it as the sole dispersion agent, since it does.

The soap dispersion agents may under some circumstances be used, but certainly not where there is an excess of alkali present, because the soap, in this case, remaining water soluble would tend to counteract the anti-foam properties of the anti-foam agent, and, moreover, in some cases, function to increase the foaming properties of the boiler water instead of decreasing them.

Investigation has shown that tannin is a very desirable dispersing agent, because at least when waters havingv alkaline constituents are treated, and particularly boiler amines.

waters, the tannin has better dispersing-properties than the clays or soap, while at the same time it does not have the disadvantages of the latter classes of materials.

. It may be pointed out that tannin in certain cases and in certain types of waters, has fairly good anti-foam properties and, therefore, the use of tannin in conjuncprimary anti-foam material, and this is highly desirable in a good anti-foam composition. Again, the tannin performs the function of conferring upon the resulting composition non-corrosive properties. This is due to the tendency of the tannin extract and similar materials to absorb dissolved oxygen from the boiler feed Water or from any other water containing oxygen, which oxygen, if not removed, is one of the principal causes of boiler corrosion. Tannin, of course, is an example of a material which is an active dispersing medium and also acts as a corrosion inhibitor to prevent corrosion of the boiler metal. It is Within the province of the present invention in its broad form to use other equivalent materials which perform the same functions as the tannin performs.

Thecomposition may have present a viscosity-increasing'agent or bodying material. A number of compounds may be used as the bodying agent, but itis preferable to use corn meal or a material containing starch. The cornmeal or starch acts not only as a bodying material, but also as an additional dispersing agent and increases the dispersion characteristics of the composition. In accordance with one form of the present invention, the antifoam composition has present a primary dispersion agent, and a secondary dispersion agent, the'secondary dispersion agent preferably acting also as a bodying agent or to increase the viscosity of the anti-foam composition, which, of course, contains anti-foam agents, as hereinbefore pointed out.

The increase in the viscosity of the anti-foam composition is desirable since this prevents separation of, the

'6 tains the amino group NH When two hydrogen are replaced,-the secondary amine is represented by RR 'NH,, and contains an imino group; and when three hydrogen are replaced, the tertiary amine is formed having the formula: RRRN.

Since it is desired that the amines be insoluble in the water treated and do not steam distill to any substantial extent, when boiler water is being treated, it is desirable and in fact practically necessary, that the amines have ahigh molecular weight of the character herein set forth. The amines having a relatively low molecular weight are soluble in the boiler water, or other water, steam distill to an appreciable extent. It is recognized that the branching of the chain in the chain amines lowers the boiling points of even the high molecular weight amine compounds having at least eleven carbon atoms in the basic, R, R or R" group. However, if the boiling point is not greatly reduced, these branch chain compounds may be used in the treatment of boiler water. For the above reasons,'in the preferred form of the invention, the compounds coming Within the scope of the present invention, should have at least eleven carbonatoms in the basic alkyl group and preferably in each alkyl group of the secondary and tertiary amines.

The following is an illustrative example of how the present invention may be carried out, there being utilized,

in'addition to the amine'anti-foarn agent, a dispersing agent and/or a bodying agent. While it may not be necessary in some instances to use a dispersing and/or tended to cover amines of the character set forth having active anti-foam constituents from the remainder of the composition.

The following are examples of methods which may be used to obtain the bodying effect.

In one method the meal or starch is heated in the presence of added water or that contained in the liquid tannin extract to a temperature high enough to produce a hydrolysis of the meal. This hydrolyzed meal upon cooling takes on the form of starch paste and acts to increase the viscosity of the anti-foam composition in proportion to the amount of starch or meal used. The amount of eleven (11) or more carbon atoms. The higher amines of the series (C H Q NH where y=0, 1 or 2, which have given very satisfactory results are heptacedyl amine, stearyl amine, secondary stearyl amine and tertiary stearyl amine. Polysubstituted amines and particularly those having eleven (11) or more carbon atoms present in 40 been obtained by heating the mixture to about 180 F.

bodying agent used in the anti-foam composition may, I

of course, vary.

In carrying out the present invention, the primary, secondary or tertiary anti-foam agent may be a simple amine saturated or unsaturated, or a mixed amine, saturated or unsaturated. Further, the primary anti-foam agent may be a mixture of simple amines saturated or unsaturated, or a mixture of mixed amines, saturated or unsaturated. The amine compound or the free amine may be formed in situ by decomposition of a suitable salt, said salt upon being added to the water, converting at least a part of the free salt to the free amine.

The compounds whichare useful in carrying out the present invention are generally represented by the following formula:

R-N-R In said formula, R denotes an alkyl group; R and R", represent hydrogen, or an alkyl group. This formula is intended to cover the primary, secondary and tertiary When one hydrogen is replaced in NH the resulting compound may be designated RNH which con- Higher temperatures maybe used. This mixture is fed into the boiler in the form of a water suspension.

As indicated, the preferred form of the anti-foam composition for introduction into the boiler feed water is that of a gelatinized product. Such a 'gelatinized composition may be made by mixing together an amine, such as heptadecyl amine, stearyl amine, or any other amine or amine mixture herein set forth with corn meal and tannin extract.

The ingredients may be mixed in suitable proportions, of which the following Tables I to IV are illustrative:

Table I (1) Corn meal2%, tannin extract94%, amine--,4%

(2) Corn meal-4%, tannin extract-88%, amine8%'- (3) Corn meal6%, tannin extract78%, amine16% (4) Corn meal8%, tannin extract67%, amine25% (5) Corn meal-8%, tannin extract57%, amine35% above set forth and still come within the spirit of the As hereinbefore pointed out, the pripresent invention. mary anti-foam base, such as the aliphatic amine, may

be used by itself, but it is desirable that the primary anti-foam agent be used in conjunction \w'th the tannin, as the tannin assists in the dispersion, and further is in itsel-fan anti-foam agent. atinized product of the ingredients, but here again, it is Within the spirit of the present invention to use the primary anti-foam agent in an anti-foam composition which is not reduced to paste form.

Instead of using corn meal or starch as the viscosityincreasing or bodying agent, various other such agents may be used, as for example, dextrine. When using dextrine, satisfactory results have been obtained when the mixture contained from 5% to 50% of dextn'ne, which is a degradation product of starch. Instead of using corn meal, starch or dextrine, other bodying agents maybe used. Gums, such as gum tragacanth, gum acacia and locust bean gum, which are additional examples of suitable bodying agents, give good results. i

-The following examples illustrate how the dispersion agents and the bodying agents may be varied:

Table II Amine Tarmin extract Corn meal Percent Percent Percent Table III Amine Tannin Benton- Corn extract ito starch Percent Percent Percent Percent 2 87 5. 6. 0 84 5. D 6. O 70 5. 0 6. 0 74 5. 0 6. 0 70 5. 0 6. 0 61 5. 0 6. D 55 5. 0 6. 0

Table IV Amine Tannin extract British gum Percent Percent Percent It is desired to point out that the above examples are merely illustrative of suitable combinations of dispersing agents and bodying agents with the amines, and that various other dispersing agents and bodying agents may be used and still come within the spiritof the present invention.

While usually the amount of bodying agent will vary from 2% to 8%, it may be much higher, as for example, when using d'extrine, up to about 50% by weight of the mixture may be dextrine, and again it is not necessary with some of the bodying agents that the lower limit be 2%. Less than 2% may be used, and while 2% may be considereda satisfactory lower limit for starch, if the starch is used in conjunction with other thickening agents, such asa gum; then the starch may be reduced to less than 2% It is preferred to form a gel-..

A paste mixture prepared as set forth and containing a primary anti-foam agent, a secondary anti-foaming agent, which preferably has dispersing properties, and a bodying agent of the character herein set forth may be added to boiler water to prevent foaming thereof. More specifically, any of the compositions herein set forth may be added to the boiler water in the ratio of one-quarter pound of the composition per 1000 gallons of water. The amount which may be added is strictly illustrative, and is not to be taken by way of limitation. Obviously, the amount of anti-foam material which is added to the water will depend upon the characteristics of the water. For example, in another experiment it was found that as low as one-twentieth 5 of a pound of the anti-foam composition per 1000 gallons of water was satisfactory.' In still another case two (2) pounds of the anti-foam composition per 1000 gallons of water positively inhibited the anti-foam tendency of the boiler feed. In the last named example, where the amine constitutes 35% by weight-0f the anti-foam material, the concentration of the amine is about 84 parts per million parts of water treated. Larger amounts of the amine than those indicated can also be employed where necessary, although a practical limit of 500 parts per million will be indicated, primarily for reasons of economy.

The above mixtures and similar mixtures were added to water of the character that the castor oil, previously referred to, was added, and the conditions of the tests were the same.

Tests taken immediately after the introduction of the anti-foam composition showed no foaming occurring. Tests made two and one-half (2 /2 hours after the introduction of the anti-foam material showed the foaming to be practically nil. Tests which were made after continuous heating of. the anti-foam material in the boiler water, under the above conditions, for eight (8) hours, showed a tendency to foam, which was only a small fraction of the foaming occurring before the antifoam was added. After twenty (20) hours the tendency to foam was not quite as great as that exhibited by the untreated water. Even in the presence of the anti-foam material, there is some tendency to foam, and the amount of foaming in the presence ofv the anti-foam material, may vary from a very small percentage to 25% to 40% of the foaming that occurs before the anti-foam material is added.

The compounds herein set forth give markedly superior results when treating water containing excess alkalinity. If castor oil, which is a well known anti-foaming agent for water which does not contain excess alkalinity, were used, the oil would become saponified and thereby rendered ineifective and/or harmful. In raw water and water softened in any well known manner, as for example by the lime-soda-ash process, the amines as here- -inbefore described are also effective.

character herein set forth, or a plurality of amines mixed.

therewith to form the amine anti-foam agent. The secondary amines may be mixed with a single amine or a plurality of other secondary amines, and the tertiary amines may be mixed with a single other tertiary amine,

or a plurality of tertiary amines to form the active antifoam agent. Moreover, any of the primary amines herein referred to may be mixed with any of the secondary amines or the anti-foam agent may comprise a mixture of a primary amine compound, a secondary amine cornpound, and a tertiary amine compound, or a mixture thereof. The tertiary amines may also be mixed with each other to form the active anti-foam compound. It

is not thought necessary to refer to all of the mixtures of primary amine compounds and/or secondary amine" compounds and/ or tertiary be used in carrying out the presentinvention. However, as a specific example, it may be stated that secondary stearyl amine and tertiary stearyl amine may be mixed together with the tannic compounds herein referred to and a bodying agent, and excellent results be obtained. The present application is a continuation-in-part of applications Serial Nos. 193,366, 193,367 and 193,368, all filed March 1, 1938, each of said applications being a continuation-in-part of application Serial No. 579, filed January 5, 1935.,

While starches, starch degradation products, and gum may be used as bodying agents, broadly any bodying agent may be used which will function to increase the viscosity of the mixture. The bodying agent may be a mixture of organic bodying agents or a mixture of inorganic agents, or the bodying agent may be a mixture of organic and inorganic compounds. As hereinbefore stated, it is preferred that the secondary dispersing agent, such as bentonite, and the like, act as a bodying agent.

The expression comprising introducing into the bath a composition containing as its essential anti-foam agent an aliphatic amine, or equivalent expressions, as used in some of the claims, is intended to cover the introduction of the amine into the bath or of the bath into the amine.

I claim as my invention:

[1. The process of treating water which includes adding to the water a small amount, not to exceed five hundred parts per million, of a compound chosen from the group consisting of aliphatic primary and secondary amines having at least six carbon atoms in an alkyl group thereof] [2. The method of treating water containing solids in the state of suspension to prevent said solids from deleteriously affecting the water, comprising adding to the water an aliphatic amine in an amount not exceeding 500 parts per million, said amine having at least six carbon atoms in an alkyl group thereof] 3. The method of conditioning an aqueous bath having ingredients present inducing foaming therein comprising introducing into the bath a composition containing as its'essential anti-foam agent an aliphatic amine contain-' ing at least eleven carbon atoms in an alkyl radical thereof, said amine being characterized by the properties of being insoluble in the bath, and showing little tendency to amine compounds which may ing as its' essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms in an alkyl radical thereof, said compound being characterized by the properties of being insoluble in the bath and showing little tendency to saponify with the ingredients of the bath, the anti-foam agent being present in an amount sufiicient to inhibit foaming of the bath.

[5. Boiler water containing alkaline constituents and carrying an aliphatic amine compound foam inhibitor containing at least eleven carbon atoms in an alkyl radical thereof, said inhibitor being present in an amount which inhibits foaming of the boiler water and being characterized by the properties of being substantially insoluble in boiler water, steam distilling to a negligible extentand: showing little tendency to saponify. 7. The method of conditioning an aqueous bath having an alkali constituent comprising introducing into said aqueous bath having an alkali constituent a composition containing as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms in an alkyl radical thereof and characterized by the properties of being substantially insoluble in the aqueous bath being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the bath, said amine being present in an amount suificient to R-N-R a R in which R is an alkyl group containing at least eleven carbon atoms; and R and R" are selected from the group consisting of hydrogen and an alkyl group.

9. The method of conditioning boiler water comprising introducing into said boiler Water a composition containing a dispersing agent, and as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms in an alkyl radical thereof and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water, said amine being present in an amount sufiicient to inhibit foaming of the boiler water.

10. The method of conditioning boiler water comprising introducing into said boiler water a composition containing a tannin dispersing agent, and as its essential antifoam agent an aliphatic amine containing at least eleven carbon atoms and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water, said amine being present in an amount sufiicient to inhibit foaming of the boiler water.

a 11. The method of conditioning boiler water comprising introducing into said boiler water a composition containing as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms, a dispersing agent for said amine and a bodying agent for increasing the viscosity of the composition, said amine being present in an amount sufficient to inhibit foaming of the boiler water and characterized by the properties of being substantially insoluble in the boiler Water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water. v

12. The method of conditioning boiler water comprising introducing into said boiler water a composition containing as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms, a tannin dispersing agent for said amine and a bodying agent for of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water.

13. The method of conditioning boiler Water compris ing introducing into said boiler water a composition containing, as its essential anti-foamagent an aliphatic amine containing at least eleven carbon atoms, a tannin dispersing agent for said amine and a carbohydrate bodying agent for increasing the viscosity of the composition, said amine being present in an amount sufficient to inhibit foaming of the boiler water and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify'with the ingredients of the boiler water.

14. The method of conditioning boiler water comprising introducing into said boiler water a composition containing' as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms, a dispersing agent for said amine and a carbohydrate bodying agent for increasing the viscosity of the composition, said amine being present in an amount suflicient to inhibit foaming of the boiler water and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water.

15. The method of conditioning boiler water which has been softened by the lime-soda process comprising introducing into said water which has been softened by the lime soda process a composition containing as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms in an alkyl radical thereof and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water, said amine being present in an amount sufficient to inhibit foaming of the boiler water.

16. The method of conditioning'boiler water which hasbeen softened by treatment with a zeolite comprising introducing into said water which has been softened by treatment with zeolite, a composition containing as its essential anti-foam agent an aliphatic amine containing at least eleven carbon atoms in an alkyl radical thereof and characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water, said amine being present in an amount sufficient to inhibit foaming of the boiler water.

' 17. An anti-foam composition for treating boiler water to inhibit foaming therein, said composition comprising as its essential anti-foam agent an aliphatic amine compound containing at least eleven carbon atoms, a tannin as a dispersing agent, and a bodying agent which increases the yiscosity of the composition and which inhibits the separation of the anti-foam constituents from the composition, said amine compound being characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with theingredients of the boiler water, said amine compound being present in an amount which does inhibit foaming.

18; An anti-foam composition for treating boiler water to inhibit foaming therein, said composition comprising as its essential anti-foam agent an aliphatic amine compound containing at least eleven carbon atoms, a tannin as a dispersing agent, and a carbohydrate bodying agent to increasethe viscosity of the composition, said amine compound being characterized by the properties of being substantially insoluble in the boiler water being treated, steam distilling to a negligible extent, and showing little tendency to saponify with the ingredients of the boiler water.

19. The method of conditioning an aqueous bath having present ingredients inducing foaming therein, com prising introducing into the bath a compositio'ncontaiming as its essential ariti-foam agent a mixture of primary,

tion containing as its essential anti-foam agent a mixture ofprimary, secondary, and tertiary aliphatic amines, each of said amines containing at'least eleven carbon atoms in an 'alkyl radical thereof, said mixture of amines being characterized by the properties of being insoluble in the boiler water, and showing little tendency to saponify with the ingredients of the boiler Water, the anti-foam agent being present in an amount which does inhibit foaming of the boiler water.

21. The methodof conditioning an aqueous bath having present ingredients inducing foaming therein, comprising introducing into the bath a composition containing as its essential anti-foam agent a mixture of secondary and tertiary aliphatic amines, each of said amines containing at least eleven carbon atoms in an alkyl radical thereof, said mixture of amines being characterized by the properties of being insoluble in the bath, and showing little tendency to saponify with the ingredients of the bath, the anti-foam agent being present in an amount which does inhibit foaming of the bath.

22; The method of conditioning boiler Water having present alkaline ingredients inducing foaming therein, comprising introducing into the boiler water a composition containing as its essential anti-foam agent a mixture of secondary and tertiary aliphatic amines, each of said amines containing at least eleven carbon atoms in an alkyl radical thereof, said mixture of amines being characterized by the properties of being insoluble in the boiler water, and showing little tendency to saponify with the ingredients of the boiler water, the anti-foam agent being present in an amount which does inhibit foaming of the boiler water.

23. The method of conditioning an aqueous bath having present ingredients inducing foaming therein, comprising introducing into the bath a composition containing as its essential anti-foam agent an aliphatic amine characterized by the properties of being substantially insoluble in the aqueous bath being treated, steam distilling to a negligible extent and showing little tendency to saponify with the ingredients of the bath, the amine compound being present in an amount sufiicient to inhibit foaming of the bath, said amine compound being represented by the following formula:

in which R is an alkyl group containing at least eleven carbon atoms; and R and R-' are selected from the group consisting of hydrogen and an alkyl group.

24. The method of conditioning an aqueous bath having ingredients present inducing foaming therein comprising introducing into the bath stearyl amine.

25. The method of conditioning an aqueous bath having ingredients present inducing foaming therein comprising introducinginto the bath a mixture of stearyl amine, tannin, and a carbohydrate which increases the viscosity of the mixture, said stearyl amine being present in an amount sufficient to inhibit foaming of the bath.

26. The method of conditioning boiler Water having present ingridents inducing foaming comprising introducing into the boiler water a compound selected from the group consisting of a substantially water-insoluble heptaamine readily hydrolyzabie into the free amine.

27. Boiler water containing alkaline constituents and carrying as an inhibitor of foaming [heptadecyl amine] a compound selected from the group consisting of a substantially water-insoluble heptadecylamine (C H NH and salts of said heptadecylamine readily hydrolyzable into the free amine.

[28. The process of treating water which includes adding to the water in an amount not in excess of 500 parts per million, a compound selected from the group consisting of aliphatic primary and secondary amines and salts of such amines readily hydrolyzable into the free amines, said amines having at least eleven carbon atoms in an alkyl radical thereo) per molecule] 29. The method of treating water containing solids in the state of suspension to prevent said solids from deleteriously affecting the water, comprising adding to the water an aliphatic amine in an amount not exceeding 500 parts per million, said amine having a total of at least elevent carbon atoms in an alkyl radical thereof per molecule.

30. The method of treating boiler water having a tendency to foam on boiling which comprises dispersing into said water in an amount not in excess of 500 parts per million, an amine selected from the group consisting of aliphatic primary amines, aliphatic secondary amines, and mixtures of said primary amines and secondary amines, said amine containing at least eleven carbon atoms in an alkyl radical thereof per molecule, and boiling the resulting dispersion.

[31. A method as claimed in claim 28 wherein the a-lkyl radical is an octadecyl radical] 32. The process of treating water which includes adding to the water in an amount not in excess of 500 parts per million, a compound selected from the group consisting of substantially water-insoluble aliphatic primary and secondary amines and salts of such amines readily hydrolyzable into free amines, said compound having the formula in which R is an unsubstituted alkyi group, R is a hydrogen atom, and R" is selected from the group consisting of an unsubstituted alkyl. group a hydrogen atom, one of said unsubstituted alfkyl groups having at least eleven carbon atoms per molecule.

33. The process of treating water which comprises adding to the water in an amount not in excess of 500 parts per miiiiou, a compound seiected from the group consistiug of substantially water-insoluhie primary and secondary aiiphatic amines having 13 carbon atoms and salts of such amines readily hydrolyzabie into the free amines, said compound having at least eleven carbon atoms in an aikyi radical thereof per molecule.

34. The process of treating water which comprises adding to the water in an amount not in excess of 500 parts per miliion, a compound selected from the group consisting of a substantially water-insoluble octadecylamine ({I I I NH and salts of said octadecylamine readily hydrolyzable into the free amine.

35. The process of treating Water which comprises dispersing into said water in an amount not in excess of 500 parts per million, a compound selected from the group consisting of a substantially water-insoluble octadecylamine (C1gII37NH2) and salts of said octadecylamine readily hydrolyzable into the free amine, and boiling the resulting dispersion.

References Cited in the file of this patent or the original patent UNITED STATES PATENTS 1,981,634 Richardson Nov. 20, 1934 1,981,635 Clarkson Nov. 20, 1934 2,074,380 Flett Mar. 23, 1937 FOREIGN PATENTS 716,560 France Dec. 23, 1931 782,930 France Mar. 25, 1935 OTHER REFERENCES Sharples Synthetic Organic Chemicals, 1937, 10th ed., page 28. 

